JOHANNESBURG, SOUTH AFRICA—Lee Burger of the University of Witwatersrand has taken a team into South Africa’s cramped Rising Star cave system to retrieve unidentified hominid fossils. “Our aim is to get the fossils out carefully, study them, compare them to other fossil material from around the world, and then proceed to analyze and describe them,” he said. In 2010, Berger announced his son’s discovery of an Australopithecus sediba fossil at Malapa Cave, located just a few miles away.